Adult Pop Songs*** No. 1 (1 week)*** "Best Day Of My Life" American AuthorsSpotlighted as recently as late November in Billboard's "Bubbling Under" feature heralding rising new acts, American Authors earn their first No. 1 on an airplay chart, as "Best Day of My Life" lifts 2-1 on Adult Pop Songs. First released on the Brooklyn band's self-titled EP, which topped Heatseekers Albums for two weeks in January/February, the song doubles as the lead track from its debut full-length "Oh, What a Life," due on next week's Billboard 200 and Top Rock Albums charts. The song is a band's first career-opening single to rule Adult Pop Songs since the Lumineers' "Ho Hey," which led for eight weeks and became the format's top title of 2013.